Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
CO₂ emitted (kg)
900
CO₂ (tonnes)
0.90
Offset cost
$16.20
Tree-years to absorb
43
Per passenger (kg)
900
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter flight distance (km).
- 2Enter passengers.
- 3Enter cabin class.
- 4Enter trip type.
- 5Enter offset price ($/tonne).
- 6Read your co₂ emitted (kg) on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Air travel emits roughly 0.09 kg CO₂ per passenger-kilometre in economy, more in business class. This estimates the footprint and offset price.
Worked example
Using the values the calculator loads with:
Inputs
- Flight distance: 5000 km
- Passengers: 1
- Cabin class: Economy
- Trip type: Round trip
- Offset price: 18 $/tonne
Results
- CO₂ emitted (kg): 900
- CO₂ (tonnes): 0.9
- Offset cost: $16.20
- Tree-years to absorb: 43
- Per passenger (kg): 900
What each field means
Inputs
- Flight distance (km)
- The flight distance used in the calculation, measured in km. Starts at 5000 km so you have a working example on load.
- Passengers
- The passengers used in the calculation. Starts at 1 so you have a working example on load.
- Cabin class
- Pick the option that matches your situation — the maths changes per option. Choices: Economy, Premium economy, Business, First.
- Trip type
- Pick the option that matches your situation — the maths changes per option. Choices: One way, Round trip.
- Offset price ($/tonne)
- The offset price used in the calculation, measured in $/tonne. Starts at 18 $/tonne so you have a working example on load.
Results
- CO₂ emitted (kg)
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- CO₂ (tonnes)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Offset cost
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Tree-years to absorb
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Per passenger (kg)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the flight carbon footprint calculator work?
Air travel emits roughly 0.09 kg CO₂ per passenger-kilometre in economy, more in business class. This estimates the footprint and offset price. The underlying maths is: CO₂ = km × factor × class multiplier
What do I need to enter?
5 values: flight distance, passengers, cabin class, trip type, and offset price. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the co₂ emitted (kg) result mean?
It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary.
Who is this tool for?
It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Flight Carbon Footprint Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/flight-carbon
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/flight-carbon" target="_blank" rel="noopener">Flight Carbon Footprint Calculator — RevenueLab</a> (2026).</p>
Source: [Flight Carbon Footprint Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/flight-carbon) (2026).